A conventional data processing system may include at least one central processing unit (CPU) and at least one graphics processing unit (GPU). The CPU and the GPU may reside on the same chip, or they may reside on separate chips that are connected by one or more buses. A single chip that contains at least one CPU and at least one GPU may be referred to as an accelerated processing unit, an advanced processing unit, or an APU. The GPU in a data processing system may operate at a different frequency than the CPU.
As indicated at the Wikipedia entry for “dynamic frequency scaling,” the voltage required for stable operation of a circuit is determined by the frequency at which the circuit is clocked, and it may be possible to reduce the required voltage if the frequency is also reduced.
The present disclosure describes methods and apparatus for dynamically adjusting GPU frequency and voltage. Data processing systems may use the disclosed technology to achieve more energy efficient operation than conventional data processing systems.